CVE-2026-42831

Heap-based buffer overflow in Microsoft Office allows an unauthorized attacker to execute code locally.

CVSS v3 7.8 HIGH

7.8^/10

CVSS v3 : HIGH

Vector :

Exploitability : 1.8 / Impact : 5.9

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-42831	Vendor Advisory

Configurations

Configuration 1 (hide)

OR	cpe:2.3:a:microsoft:365_copilot::::::android::*
	cpe:2.3:a:microsoft:office:2024::::ltsc:macos::*
	cpe:2.3:a:microsoft:office_long_term_servicing_channel:2021:::::macos::

History

No history.

Information

Published : 2026-05-12 18:17

Updated : 2026-06-17 10:48

NVD link : CVE-2026-42831

Mitre link : CVE-2026-42831

CVE.ORG link : CVE-2026-42831

JSON object : View

Products Affected

microsoft

365_copilot
office
office_long_term_servicing_channel

CWE

CWE-122

Heap-based Buffer Overflow

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